In-situ analysis of Li-ion batteries via neutron diffraction

Feasibility of in-situ neutron diffraction analysis on a commercial Li-ion cell (Sony 18650) has been demonstrated. Time-of-flight (TOF) neutron diffraction data collected on this commercially packaged Li-ion battery indicated a weak but detectable signal from the LiCoO2 cathode. Refined lattice parameters for the LiCoO2 cathode indicated that the unit cell expands along the c-axis and contracts along the a-axis, with an overall unit-cell volume expansion during charging from 3.6V to 4.IV. In-situ neutron diffraction is a useful technique for measuring structure/property relationships on Li-ion batteries. Straightforward improvements in experimental design may significantly improve results of future measurements.